1. Field of the Invention
The present invention relates to a user interface, more particularly to a user interface that detects a double tap.
2. Description of the Related Art
A manipulation panel is provided as a user interface in a general image forming apparatus, such as an MFP (Multi Function Peripheral). The manipulation panel includes a display unit, such as an LCD (Liquid Crystal Display), which displays a software key and various pieces of information, a touch panel that is disposed to receive a manipulation of user's finger while overlapping a front surface of the display unit, and a hardware key that is provided around the display unit. When a tap, which is an operation to touch the touch panel and separate the finger from the touch panel, is performed to a software key displayed on the display unit, the touch panel outputs instruction information allocated to the software key.
The software key is a key group displayed on the touch panel. The user manipulates the software key by touching a predetermined domain of the touch panel display. The software keys to which various functions are allocated are displayed into various shapes on the touch panel display, and the software keys are erased when a need for the software keys is eliminated. The hardware key is a button-shaped key group including a physical substance. The user manipulates the hardware key by pressing the hardware key.
In the case that a trouble (for example, paper out, a jam, and a network connection failure) is generated in the image forming apparatus, the manipulation panel automatically displays a message notifying the user of the trouble on the touch panel in response to an instruction of the image forming apparatus. For example, the message is displayed in a pop-up format.
For example, Documents 1 and 2 described below disclose a technology related to the touch panel. In the technology disclosed in Document 1, in the case that the user touches a selection icon on the touch panel, the touched selection icon is specified based on a coordinate information from the touch panel, and a determination icon corresponding to the selection icon is displayed in a domain adjacent to the selection domain in an overlapping manner. When the user touches the determination icon, the selection of the selection icon is fixed.
Document 2 discloses the following technology. A display controller displays a key image that is a manipulation target on the display unit. A receiving domain (domain information) corresponding to the displayed key image is stored in a domain storage unit. A detector detects the touch manipulation performed by the user, and detects a touch position. A determination unit determines whether the touch position exists within a range of the receiving domain stored in the domain storage unit. A timing unit measures an elapsed time after the touch manipulation. A domain controller enlarges the receiving domain of the touch position to a predetermined range when the touch manipulation is detected, and the domain controller reduces the enlarged receiving domain to the original size when the timing unit measures the elapsed time.    Document 1: Japanese Patent Publication Laying-Open No. 2009-048245    Document 2: Japanese Patent Publication Laying-Open No. 2009-003851
A double tap is one of the manipulations performed in the touch panel by the user. The double tap is a manipulation in which a tap, which is an operation to touch the touch panel and separate the finger from the touch panel, is continuously performed twice. According to the double tap, any software key is selected by a first tap, and a function related to the selected software key can be performed by a second tap, and operability of the user can be enhanced.
FIG. 18 is a view schematically illustrating a transition of the screen displayed on the display unit when the touch panel detects the double tap in the related art.
Referring to FIG. 18(A), the manipulation panel displays the box selection screen on the display unit. The manipulation panel displays a document box, which is stored in a box of the image forming apparatus, as an icon. When the user taps twice an icon C101 of a box named “design idea report” having a box number “00000009”, the touch panel detects the double tap. When the touch panel detects the double tap, the manipulation panel displays a list of files stored in the box named “design idea report” on the display unit as illustrated in FIG. 18(B).
However, unfortunately the operability of the double tap is insufficient in the related art.
FIG. 19 is a view schematically illustrating a transition of the screen displayed on the display unit when a message giving a warning about an abnormal situation of the image forming apparatus is displayed in the related art.
Referring to FIG. 19, conventionally until the touch panel detects the second tap since detecting the first tap in the double tap as illustrated in FIG. 19(A), sometimes the manipulation panel displays a warning message M101 giving the warning about the abnormal situation of the image forming apparatus on the display unit in the pop-up format as illustrated in FIG. 19(B). Therefore, pop-up warning message M101 is displayed while interrupting the double tap, and sometimes the second tap is not detected by the interruption of warning message M101.
The above problem is not limited to the user interface of the image forming apparatus, but the problem is possibly generated in all the user interfaces.